1971-2010年京津冀大城市热岛效应多时间尺度分析

Multi-Time Scale Analysis of Megacities Heat Island Effect in Beijing-Tianjin-Hebei Region from 1971 to 2010

利用1971-2010年均一化的京津冀区域逐日气温数据与质量控制后的2011年自动站逐时气温数据,分析了北京、天津和石家庄热岛效应的多尺度时间变化特征。结果表明,三个城市平均、最高和最低气温的热岛效应呈非对称性特征,最强为最低气温的热岛效应,其次为平均气温的热岛效应,最弱为最高气温的热岛效应。北京平均气温的热岛效应最强,其次为天津,石家庄相对较弱,石家庄平均气温的热岛效应近40年呈显著上升趋势,每10年达0.13℃。石家庄最高气温的热岛效应最强,其次为北京,最小为天津,近40年北京最高气温的热岛效应呈缓慢上升趋势,每10年增加0.06℃,石家庄变化不明显,天津呈微弱下降趋势。最低气温的热岛在北京最强,其次为天津,最小为石家庄,近40年最低气温热岛效应天津呈明显上升趋势,每10年增加0.18℃,其次为石家庄,北京呈微弱下降趋势。三个城市的平均气温、最低气温的热岛效应季节变化通常表现为夏季较弱,冬季最强。三个城市最高气温的热岛效应季节变化差异较大,北京10月热岛效应最弱,其他月份变化不大;天津热岛效应6月最弱,在1或12月最强;石家庄4和5月热岛效应最强,10月热岛效应最弱。由2011年自动站数据得到的平均气温热岛效应与1971-2010年的40年平均得到的平均气温的热岛效应季节变化具有类似的规律。2011年自动站热岛效应在一天中表现为白天热岛强度较低,而夜间热岛强度较高。

Based on a homogenized daily air temperature dataset from 1971 to 2010 and quantity controlled hourly air temperature data of Beijing-Tianjin-Hebei Region in 2011,the multiscale temporal characteristics of urban heat island effect for Beijing,Tianjin and Shijiazhuang are analyzed in this paper.The results show that the urban heat island effect on the mean,maximum,minimum air temperature is asymmetrical.The heat island effect on the minimum temperature is the strongest,followed by the effect on the mean temperature and the effect on the maximum temperature is the weakest.The mean temperature in Beijing is affected by urban heat island effect most significantly,followed by Tianjin＇s.Shijiazhuang＇s heat island effect is relatively weak,but showing the trend of significantly increasing during the late 40 years,up to0.13°C every 10 years.For the maximum temperature,urban heat island effect in Shijiazhuang is the strongest,followed by Beijing＇s.Tianjin＇s heat island effect is relatively weak.Beijing＇s heat island effect on maximum temperature increases slowly during the 40 years,being 0.06°C every decade.No significant change in Tianjin.Shijiazhuang＇s heat island effect shows a weak downward trend.For the minimum temperature,Beijing＇s heat island effect is the strongest,then is Tianjin＇s.Shijiazhuang＇s heat island effect is the weakest.Tianjin＇s heat island effect on lowest temperature increases in the 40 years,0.18°C every decade.Tianjin has no significant change,followed by the Shijiazhuang＇s.Beijing＇s heat island effect shows a slight downward trend.Generally,the three cities heat island effect intensities for mean and maximum air temperature are characterized by weak in summer and strongest in winter,for maximum temperature,they are different with change of seasons.The seasonal heat island effect from automatic weather station is similar to the heat island effect calculated from the data in 1971 — 2010.The heat-island effect in a day is characterized by low during the daytime and high during the nighttime.